


Embers (CasGil)

by OjouOfFrance



Series: Sin Bits of Chaldea [3]
Category: Fate/Grand Order
Genre: Budding Love, F/M, Internal Conflict, Master/Servant, Oral Sex, Sex, Vaginal Sex
Language: English
Status: Completed
Published: 2020-05-01
Updated: 2020-05-01
Packaged: 2021-03-02 01:35:46
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,234
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/23947042
Author URL: https://archiveofourown.org/users/OjouOfFrance/pseuds/OjouOfFrance
Summary: The Caster King of Uruk has no trouble figuring out what his body desires, but what of his heart?
Relationships: Gilgamesh | Caster/Reader
Series: Sin Bits of Chaldea [3]
Series URL: https://archiveofourown.org/series/1722262
Comments: 15
Kudos: 171





	Embers (CasGil)

**Author's Note:**

> This is Female Reader as usual. Please enjoy!

It had been a close dodge. Gritting his teeth, the King of Heroes didn’t expect such a challenge from such mindless monsters, namely that their armour would be resistant to his magic. Pulling up the tablet at his side, he shot another blast from the Gate of Babylon, watching some fall as others got up, ready for another round. It didn’t help that his mind was partially distracted, an eye always on his reckless master as she charged here and there providing support with her limited mana, her magic also not doing much damage to the brutes, but at least being able to stun them for a time. 

His distraction was getting the better of him, surprised as he felt a large hand whack him aside, tumbling on the ground, cursing as he knelt up, trying to recuperate as he spat the blood of a busted lip on the ground. Then, as he spotted a lance coming toward him, about to recite another incantation to open the Gate, he paused, eyes wide as the lance was deflected with magic, a sudden figure standing in front of him. As he looked up, he saw his little master panting harshly, defending him as she held a damaged shoulder, seeing the blood through her shirt.

Reflexively he shouted out, “Fool! What are you doing?! Get out of the way!”

“Shut up!” she yelled back, sending another wave of magic to the hoards. 

He knew that they had to get serious or they would fail their mission at this rate. He glanced to her a moment, asking a little more calmly, “How much mana have you left?”

She paused a moment, clicking in her mind what he was asking, and standing firm. “Enough. Please hurry, we need to take care of them. Will it be enough to finish them off?”

He stood up, coming over and standing in front of her, a look of slight annoyance and challenge on his face as he tilted his head to her. “Who do you think I am? Am I not Gilgamesh, Great King of Uruk, King of Heroes?”

She nodded, closing her eyes, passing her mana to him as he charged up his energy, slowly floating up as his tablet opened before him in mid-air, ancient runes glowing around him as he uttered, “Hear my voice. All gun ports, open!”

The Gate of Babylon opened further to reveal the sturdy stone wall of Uruk itself, the will of the people ready to head the call of their king as he commanded them.

“Ready your arrows, for I shall allow it! Show them well the superior assets Uruk’s defenses possess! May our eternal determination rain upon the Earth!

Melammu Diĝir!”

In the next moment a shower of mystic arrows rained down upon the monsters below, slaying them in droves, their cries echoing through the flames of the town around them. 

Once the monsters had all been defeated, and activity went quiet, the only sound came from the scorching blaze. Giving a sigh, the mighty king descended back to the ground, his master watching him land before turning her gaze to the fire. Most of the residences were either evacuated or already dead in the flames or by the beasts that had attacked their village. They had been unprepared, hadn’t expected the monsters’ armour able to neutralize her caster’s powerful magic. The gnawing feeling didn’t sit well with her. 

“Come” his voice broke her train of thought as she looked up to him, his gaze on her, “There’s nothing left here. We’ve finished our mission.”

Despite his words, she still looked back to the burning town, stepping forward and using her magic to try and quell some of the flames.

“What are you doing?” He snarled, “This town is already destroyed, there’s nothing left! If we do not leave now, we risk endangering this mission!”

“Maybe, but there’s another town not far.” She retaliated, looking to him seriously. “And if their town should catch fire and burn because we could have put out the flames and chose not to?”  
He looked to her for a moment, unwilling to back down, until he gave an exacerbated sigh, though his gaze lingered on her a moment. “Let’s hurry then. The longer we stay, the more chances of something else happening.”

**************************************************

As he sat alone in his room in Chaldea that night, with a book in one hand that he only glanced over passively, his mind resting on the earlier mission. Flashes of her face, determined and stubborn as usual passed over his mind as he sighed to himself, wondering in silence why he felt transfixed on it. What a fool she was, that master. She had stood in his way when she was injured in a futile attempt to defend him, she had exhausted herself with overusing her mana, and of course she refused to listen to him, her King. He clicked his tongue thinking about it, becoming slightly irritated as he remembered her telling him to shut up. 

Then he remembered her rational about the town, how she went on despite the end of the mission, and thought about what she did during the plight of his own people. She had done the same back then, sacrificing everything for humanity…was it something else? Why did she insist on staying during the mission today? Humanity was not under threat, there was no Beast, and it was just another town, not the foundation of the future of humanity. He had even suggested they leave, so then why… was he perhaps overthinking it? No, there had to be something to it.

“King?”

Hearing that title snapped him out of thought as he turned his head, seeing her come into the room, getting him to emit an irritated growl.

“Is this now your room? I don’t recall inviting you in!” 

“I know, but I wanted to talk about today.”

Her tone was somber and he was curious, eventually allowing her to come over. However, despite turning to face her, his legs crossed as he sat on one of his many luxurious pillows that filled his room, he despaired as she insisted on sitting in his lap.

“What impudence! Treating your King like a chair!”

“Oh hush” she scoffed, getting comfortable on his lap, noting that he wasn’t pushing her away, as she predicted, a little smile over the happiness that fact brought her.

He sulked, wrapping an arm about her as if instinctual, leaning his chin in his free hand, asking, “Very well, I will show you some generosity, stubborn little thing you are. What is it?”

“About today…” she trailed off, fiddling with her sleeve a moment, as if not quite sure how to address it.

“Speak quickly or leave!” he warned.

“S-Sorry!” she jumped a little surprised, “It’s just… I know you wanted to leave after the mission, and it was wrong of me to pressure you to stay like that. To hang that guilt over your head, it was blackmail, and I’m sorry. You always do so much for me, and even though I know it’s hard sometimes, and I don’t listen a lot, and even though you’re a pain sometimes-“

“Get to the point!” he barked and she flinched a little as he interrupted.

“I just wanted to say… Thank you for staying Gil. You could have left me there, but you didn’t.”

“Humph, were a King to leave behind even a single subject, can he call himself King?” he replied haphazardly as though it was nothing.

She turned, reaching up to brush a hand along his cheek, catching him off-guard as he froze, eyes going wide. 

“I mean it Gil, thank you. I don’t say it often, but… I really care about you. I really want you to know how much I treasure you.”

Those words, so sweet and foreign to him, seem to bring his cognition to a halt, his eyes fixed on her as he appeared frozen in time. This was a joke, right? This sweet, loving treatment. He felt his heart erratic in his chest and couldn’t explain it. It was so different to anything he felt and he couldn’t believe it was anything but a trick. 

The longer he hesitated in saying anything, the more nervous she became. She felt her face beginning to flush, seeing his shock, “King? Are you ok? I’m sorry, I shouldn’t have touched you if you didn’t-” Then she became even more flustered as his face began to turn red bit by bit, sputtering out, “Ah! Gil?! Are you alright? Say something!”

He had to take a breath to calm himself, try to reclaim his thoughts, but by now he couldn’t control the colour on his face, saying sternly, “You…. Shouldn’t use such words lightly, Mongrel. However, if that’s how you feel, I suppose I’m not one to deny you that.”

Suddenly, seeing his embarrassment she broke from her nervousness into an amused grin, giggling lightly, “Aw, I’m sorry Gil, are you a bit embarrassed? It’s kind of cute!”

“Silence!!” he insisted, only making her laugh more.

“Okay! I’m sorry! I’m sorry!” she shouted through laughter. She then got up out of his lap, intending to walk away. “Fine, I won’t tease you anymore, I’m sorry. I’ll let you be.”

Suddenly, as she went to walk away, he took hold of her wrist, pulling her back down into his lap, one arm around her waist, his free hand catching her under her chin to have her look up into his deep red eyes, full of unseen gentleness.

“I meant it. Such words are not to be used lightly.” He almost whispered to her, making her gulp, feeling the heat in her own cheeks anew.

“I know…” she replied, “I meant them.”

“I know.” He replied surely, his crimson eyes giving a slight glow.

He bowed his head lower and lower, closing the distance for a soft yet demanding kiss, feeling the way she melted against him, almost completely giving in. As they broke, he felt the air she let out against his lips, saw the little smile she gave him.

“That’s no fair.” She muttered, “I can’t read your mind to tell how you’re feeling.”

“Then I will show you my true feeling.” He promised, tilting her chin up a bit more for a second kiss, this one more heated than the last, nibbling on her lower lip until she allowed him to slip his tongue into her mouth, feeling a shiver down his spine at the sound she made.

He made the kiss last as long as he could until he felt her hand clutching at his vest, releasing her with a gasp as she heaved slightly. Without a word, he shifted her in his hold, standing with her bridal style in his arms as she squeaked lightly. He walked over towards his bed, laying her down with a look of both exasperation and reluctant defeat, saying, “Honestly, what an unfathomable woman you are. How do you expect me to resist when you offer your heart to me so freely?”

“Oh? You think I offer it freely?” she teased, smiling before suddenly feeling him crawling on the bed over her, the weight around her shifting as he eclipsed her body on the sheets. He leaned down, entwining her hands in his, feeling him gently pull them up over her head as he gave her a smirk for a moment.

“I think you still have much to learn.” He said rather cockily, much like his other self would have before he let go of her, kneeling up to observe her from above. As she went to move to get up with him, she suddenly felt her hands held back, looking back to see the small portals of the Gate of Babylon and the gold rope that encircled her wrists.

“H-Hey!” she protested, giving him a cute pout, “That’s not fair, Gil!”

“What good is it to play fair if one cannot win?” He asked obviously, shedding his vest, then his headdress, placing it aside. He made wordless work of her clothing, shedding every layer with precision and care, as though unwrapping a gift, leaving small kisses and affectionate touches as he went, all the while he savoured the hunger building in his abdomen. He paused a moment, noticing the bandaged shoulder, but he knew she would ask if something was wrong if he didn’t continue and he didn’t have the right words for her about it right now.

Once he had every last piece off, gently sliding her panties off, he allowed himself to appreciate his little treat, licking his lips in anticipation for the possibilities while her hands were tied up. 

She felt her body flush at even his lightest touches, his lips soft and delicate on her skin, as his eyes were sharp and piercing. She gulped a little, already feeling the heat begin to build within her. He seemed to be thinking a moment before snapping his fingers in realization, a small “Ah, that’s it.” before he pulled a little something from the Gate. It looked to her like a silk scarf or something of the sort, but then before she even got a good look at it, she found herself blinded by the object as he tied it around her head, leaving her in the dark.

She shook lightly, hesitantly asking, “G-Gil? What are you doing?”

“I do as I please. And this… this pleases me.” He said smugly, leaning down to run his fingers down her bare body, loving the shivers and goosebumps he left. With the blindfold, he knew she would feel him tenfold. He leaned over, beginning at the top of her jaw, kissing down, then continuing to kiss and lick down her neck, watching her breath hitch, her body shudder, her little mewls of pleasure as she fought to no avail against the restraints. He grinned as he bit down on her collarbone, hearing the little cry she gave, feeling himself becoming harder, giving a small groan.

He continued, trailing down her body, his hands teasing as they roamed, mapping every inch of her skin, his mouth lavishing her with affection as he came to lick and suck at her breasts, amused as always at how sensitive they were, already hearing her begin to call out his name, but only in small whimpers. No, not enough, not yet. 

Once he was sure both pink peaks were hard with arousal and she was nearly begging with mercy, he continued to map out her body, her sweet body that was all his, as were all things in this world.  
He trailed down her navel, over her hips and down past her waistline, coming to the heat between her legs, already feeling the warmth from it. With a snap, he cast off the rest of his clothing, leaning down and pushing her legs apart to make room for him between them. 

She flinched as she realized what he must have been doing, stuttering, “W-Wait Gil, if you do that-!”

She froze then shivered, feeling him trail a finger from the top to the bottom of the slit, not able to see his smirk, but sure it was there. 

“I can only imagine how this will feel now that your sight has been robbed from you… shall we see?”

She didn’t even have time to reply before her body jolted, a cry from her lips as she felt a long, hard suck against her clit, her body trembling as he kept it up, almost torturing in the level of intensity as his lips and tongue focused solely on that little button. “Ahh, Gil! S-So much!” she whimpered, gritting her teeth with a choked cry as he slipped two fingers into her up to the second knuckle. She shivered as she felt him release a purring sound against her, the heat on overdrive as he focused on every weak spot simultaneously.

“Wait Gilgamesh, please! If you go so hard I-I’ll-!”

She warned him, feeling the fire burning within her overtaking her quicker than she could manage. With her lack of sight, his lips felt soft and sweet, his tongue hot and wet. She felt her wrists straining lightly against the ropes and her hips jolted and arched as he growled against her skin. She whimpered lightly, feeling his nails against her thigh, holding her apart for him to feast upon as his fingers thrust into her. Finally, feeling that coil tighten to its extreme, she tossed her head back, his lips sucking hard at her as she cried out “Gil I’m-!!”

It was sooner than expected, but as he felt her walls constrict around his fingers, eliciting a groan from him, he quickly withdrew them to watch her convulse, the sight so tantalizing as he saw the result of his work on her.

As she began to come down from her high, panting and shaking, he knelt back up, licking his lips with a sound of appreciation. He took the cloth from her eyes, seeing her blink dazedly in the aftermath of her pleasure, still full of desire. 

“That was quick.” He teased, seeing the flush on her face. “You’re rather receptive to your King’s generosity, aren’t you?”

“Oh hush…” she muttered, but then blinked, hearing him snap his fingers, releasing her hands from their bonds as they dropped freely. She felt him tugging her ankle, dragging her down slightly. He parted her legs, settling his hips between them. She blushed, seeing his hardened arousal as he placed it against her. She met his eyes, full of both lust but also something she couldn’t quite figure out, something deep. 

He leaned down, his face inches from hers, his lips centimetres from hers as they fell into each other’s eyes for a moment.

“Hold onto me.” he said, barely above a whisper, and she quickly did as he asked only moments before she felt him start to push into her, gritting her teeth, trying to muffle a loud cry to no avail.

His own growl at her tightness made her shiver, digging her nails into his back as he pushed in inch by inch until he was as deep as he could go. She panted heavily, trying to adjust to him as quickly as possible. His own heated face, crimson eyes full of desire, made her walls flutter about him as he gripped the sheets by her sides. Gods, her nails on his back should be considered sinful, but he loved it so much.

She felt the way he pulsed within her, surprised to see the affect this had on him almost as intensely as on her. “Gilgamesh…” she uttered softly, “I can feel you…so deep…mm, it’s okay, you can move.”

He didn’t even nod before he pulled out slowly, then sank back into her, groaning at the warmth of her body. He began a steady pace, savouring every thrust, watching her face as it contorted with her pleasure, feeling his arousal spike every time she whimpered or cried out his name. He leaned down, catching her in a messy kiss, drinking in her moans, her taste. When he broke the kiss, they were both drowned in bliss, panting and groaning as he reached below her knees to push her legs up to give him more space as he picked up his pace. 

He trailed his tongue along her neck, giving a slight bite where it met her shoulder, chuckling slightly at the keening cry she gave. He jolted, feeling her walls tighten about him as she dug her nails into him, the pleasure shooting through his veins.

“Why you…” He choked out.

“Gilgamesh.”

The tender way she said his name made him halt his chiding, looking to her. 

“Please,” she said, “I want more… harder. Please, my King.”

He felt his face flush with those words, his heart beating strong in his chest. Feeling a shudder run down his spine, his calculated expression turned sly, a wide grin on his face.  
“Hoh~ My little minx bares her true ambitions then? Since you’re being so obedient…”

He suddenly pulled out, making her whimper at the sudden emptiness, before quickly flipping her over on her hands and knees, gripping her hips tightly before slamming back in, now easily sliding in as she gave a loud cry. His pace was now harsher, riding her with renewed zeal as her voice called out so prettily for him, “Ahh, yes, that’s it, Gil! Gilgamesh… m-my King! I love it! I love you! Hah!”

Did she know how strongly her words lay on his heart? Perhaps not, she couldn’t read his mind like he could hers, but he could show her. He gave a loud, harsh growl as he pushed in as deep as he could, leaning over her and grasping her hips tightly in his hands, feeling the sweat and heat on her skin, trailing one hand under her to toy with her breast as she moaned and clenched him tightly. Her hands trembled in their grip of the sheets, both of them panting harshly with each hard thrust. She arched up as he rode against that spot deep inside her that sent white hot pleasure rushing through her.

“Gil…Gilgamesh, yes, please…. It feels so good!”

As he knelt above her, trying and failing to manage the amount of pleasure coursing through him, her mana slowly seeping into every crevice of his body, he noticed once more the bandage on her shoulder. Hesitating a moment, he gently bent down, bringing his lips to the bandage to kiss it, watching her jolt, sure that it must have still been a bit sore.

“G-Gil?” She asked curiously, a little concerned.

Without missing a beat, he suddenly drove into her harder, faster, his fingers on her body trailing over between her legs to circle that sensitive jewel, hearing her cry out.

“W-Wait Gil! That’s too much! Mm! If you do that, I’ll-!” she begged, and he grinned mischievously, resting his head in the crook of her neck, his hot breath dancing on her skin.

“Yes, that’s it, my foolish master. Drown yourself in bliss. Let my fingers, my body take you to your ultimate pleasure! Nn!” he groaned, feeling her fluttering about him. He knew how potent his own words were with her and took advantage of it, seeing her red face and blurry eyes. “Fall over that edge of bliss so hard as to take me with you… t-then I shall fill you with every drop of my essence!”

She whimpered softly at his words, begging him, calling his name, but it was futile. With a hard thrust against that spot deep within, his fingers on her clit and his mouth on her skin, she gripped the sheets hard, suddenly arching back, her body going stiff as she nearly screamed, her pleasure reaching its peak as she called out his name, “Gilgamesh!! Aahh!!”

The way she said his name in her utter euphoria, he couldn’t help feeling his own pleasure peak, her walls gripping around him so tightly, urging him to end with her. He thrust once more, gripping her hips tightly to keep her still as he felt himself reach his limit, releasing his hot seed deep within her as he groaned harshly against her.

Once he was finished, the two stayed together like that, shaking and recovering, their breaths harsh and worn. He recovered a bit quicker, giving a sly smile as he suddenly pulled from her, hearing her small whimper. He rolled over, laying next to her on the bed, splayed out as he looked to her. Without a word, she turned and curled against him, making him chuckle lightly. He shifted to lay on his side, his head resting in his hand as he looked to her. Her eyes fluttered, but a pleasant smile rested on her lips.

“Gilgamesh… thank you” she said softly.

“Humph, there’s no need for such trivial things.” He muttered casually, looking her over. He resisted the urge to run a hand over her face, or through her hair, but didn’t shove her away as she nuzzled against him. As he looked to her face, he noticed her eyes already closed, her breath getting even.

“Oi, I didn’t say you could sleep yet.” He complained in vain, giving a huff when she didn’t reply. Perhaps she was tired from the mission. His eyes trailed over to glance once again at the bandaged shoulder, thinking back on today’s events. She had been willing to take that for him despite being far weaker, despite knowing he could take it. What a silly thing to do, he thought. However, she had kept her calm, remained stern and level-headed. She had defended that town with her last, and even put the flames out when there was nothing left, and as he thought of his beloved Uruk he thought about how she hadn’t thought twice of doing that for him, for what he loved most. That was just who she was.

However, as the image of that unshakable spirit with a determined glow in her eyes and her steadfast smile drifted in his mind, he was grateful that she was already drifting into sleep so that she couldn’t see the heavy blush on his face that he covered in his hand.


End file.
